docs: Add comprehensive cache troubleshooting guide

- Document the root cause of cache timeout errors
- Explain all implemented solutions
- Provide step-by-step fix instructions
- Include verification and troubleshooting steps
- Add support resources and additional help

docs/CACHE_TROUBLESHOOTING.md

@@ -0,0 +1,140 @@
+# Cache Troubleshooting Guide
+
+## Problem Description
+
+The LabFusion CI/CD pipelines were experiencing cache timeout errors:
+```
+::warning::Failed to restore: getCacheEntry failed: connect ETIMEDOUT 172.31.0.3:44029
+```
+
+This error occurs when the cache service is not accessible from the job containers due to Docker networking issues.
+
+## Root Cause
+
+The issue is caused by:
+1. **Docker Networking**: Containers can't reach the cache server on the host
+2. **Random Port Assignment**: Using port 0 causes unpredictable port assignments
+3. **Cache Service Location**: The cache service binds to an IP that containers can't access
+
+## Solutions Implemented
+
+### 1. Workflow-Level Fixes
+
+Added `fail-on-cache-miss: false` to all cache actions in:
+- `.gitea/workflows/api-gateway.yml`
+- `.gitea/workflows/frontend.yml`
+- `.gitea/workflows/service-adapters.yml`
+- `.gitea/workflows/api-docs.yml`
+- `.gitea/workflows/ci.yml`
+
+This ensures that cache failures don't cause the entire pipeline to fail.
+
+### 2. Runner Configuration Fixes
+
+Created `runners/config_cache_fixed.yaml` with:
+- **Fixed Host**: `host.docker.internal` (allows containers to access host)
+- **Fixed Port**: `44029` (instead of random port 0)
+- **Host Network**: Uses host networking for better connectivity
+
+### 3. Troubleshooting Tools
+
+Created diagnostic scripts:
+- `runners/fix-cache-issues.sh` (Linux/macOS)
+- `runners/fix-cache-issues.ps1` (Windows)
+
+These scripts help diagnose and fix cache issues.
+
+## How to Apply the Fixes
+
+### Option 1: Use the Fixed Configuration
+
+1. Stop your current runner:
+   ```bash
+   pkill -f act_runner
+   ```
+
+2. Start with the fixed configuration:
+   ```bash
+   ./act_runner daemon --config config_cache_fixed.yaml
+   ```
+
+### Option 2: Run the Troubleshooting Script
+
+**Linux/macOS:**
+```bash
+cd runners
+./fix-cache-issues.sh
+```
+
+**Windows:**
+```powershell
+cd runners
+.\fix-cache-issues.ps1
+```
+
+### Option 3: Manual Configuration
+
+Update your runner configuration with these key changes:
+
+```yaml
+cache:
+  enabled: true
+  host: "host.docker.internal"  # Fixed host
+  port: 44029                   # Fixed port
+
+container:
+  network: "host"               # Use host networking
+```
+
+## Verification
+
+After applying the fixes:
+
+1. **Check Runner Logs**: Look for cache service startup messages
+2. **Test a Workflow**: Run a simple workflow to verify cache works
+3. **Monitor Cache Hits**: Check if dependencies are being cached properly
+
+## Expected Results
+
+- ✅ No more `ETIMEDOUT` errors
+- ✅ Cache hits show "✅ Cache hit!" messages
+- ✅ Faster build times due to dependency caching
+- ✅ Workflows continue even if cache fails
+
+## Troubleshooting
+
+If issues persist:
+
+1. **Check Docker Networking**:
+   ```bash
+   docker network ls
+   docker network inspect bridge
+   ```
+
+2. **Verify Cache Service**:
+   ```bash
+   netstat -tlnp | grep 44029
+   ```
+
+3. **Test Connectivity**:
+   ```bash
+   curl http://host.docker.internal:44029/
+   ```
+
+4. **Check Runner Logs**:
+   ```bash
+   tail -f runner.log
+   ```
+
+## Additional Resources
+
+- [Gitea Act Runner Documentation](https://gitea.com/gitea/act_runner/src/branch/main/docs/configuration.md)
+- [GitHub Actions Cache Documentation](https://docs.github.com/en/actions/using-workflows/caching-dependencies-to-speed-up-workflows)
+- [Docker Networking Documentation](https://docs.docker.com/network/)
+
+## Support
+
+If you continue to experience cache issues after applying these fixes, please:
+1. Run the troubleshooting script and share the output
+2. Check the runner logs for any error messages
+3. Verify your Docker and network configuration